The factors determining success with cochlear implants in prelingually deaf children are many. One such factor is the age at implantation. Previous research has suggested a sensitive period for cochlear implantation in the prelingually deaf; however, the mechanisms limiting this sensitive period are not understood. The visual system of prelingually deaf young adults has been shown to use the processing resources of the deprived auditory system. Perhaps it is this rewiring of cortical processing resources that restricts the upper limit of the sensitive period for cochlear implantation in prelingually deaf children. Once this change in sensory processing has occurred, the ability of a cochlear implant or hearing aid to restore normal auditory function to the cortex may be limited by this rewiring of sensory systems. The time course of the development of cross-modal plasticity, in relation to this sensitive period is not known. This investigation proposes to examine the time course of visual/auditory cross-modal plasticity in prelingually deaf children age 2-10, through the examination of visual evoked potentials in response to motion stimuli and auditory evoked potentials in response to speech sounds. [unreadable] [unreadable]